Improvement in lathes for turning buttons



T. JrROOKWOOD. Lathe for Turning Bu,tt0ns..

No. 214,705. Patented April 22, 18,79.

W Wm N. PETERS. PHOTO-LITHOGRAPHER, wAsNlNGTbN, D C.

UNITED STATES PATENT QFFIGE.

THOMAS J. ROCKVVOOD, OF LEOMINSTER, MASSACHUSETTS.

IMPROVEMENT IN LATHES FOR TURNING BUTTONS.

Specification forming part of Letters Patent No. 214,705, dated April22, 1879; application filed February 24, 1879.

To all whom it may. concern:

Be it known that I, THOMAS J. RocKwoon, of Leominster, \Vorcestercounty, in the State of Massachusetts, have invented certain new anduseful Improvements relating to Lathes for Turning Buttons, of which thefollowing is a specification.

It has been common in the manufacture of buttons from horn-tips andanalogous material to produce the blanks in the form of a short cylinderof proper diameter, and of a length equal to or a little in excess ofthe thickness of the button, and to give the proper swelled form to eachface and the rounded section at the edge by subsequent treatment in alathe. I have devised an improvement in such lathes, by which theoperation is facilitated.

Lathes have been before known which worked rapidly, but involved awasteof materiahwhich my invention avoids. The more common mode of treatmentheretofore has used the material economically, but involved increasedlabor. My chuck economizes both time and material.

I designate by the term chuck the holding means for the blank, and alsothe mechanical devices by which the proper opening and closing motion isimparted thereto.

My experiments have been made with that class of buttons in which thereis one hole exactly in the center on the front face and two holes in therear face converging together; buiilthe invention may apply to otherstyles as we Automatic mechanism may be used for operating thecutting-tool; but I will describe as having the cutter worked by hand.

The accompanying drawings form a part of this specification, andrepresent what I consider the best means of carrying out the invention.

Figure 1 is a side elevation of the lathe, partly in section. Fig. 2 isan end view of the chuckhead alone. The remaining figures are sectionsthrough the button-blank when partly formed and the outline of theadjacent portion of a chuck-head. These figures show the button-blank intwo positions. Fig. 3 shows the button-blank as .it is first held. Fig.4 shows the button-blank after it has been reversed in position to allowthe last side to be finished.

Similar letters of reference indicatecorresponding parts in all thefigures.

A is the fixed frame-work. B is the shaft or arbor running in fixedbearings therein, and driven by a belt (not represented) from anysuitable power. Its overhanging end B is screw-threaded on its exterior,and matches the internal threads of a separate piece, D, which forms thebody of my chuck. The outer end is slotted longitudinally, and in theslots are mounted levers turning on pins 6. There may be various numbersof these levers. I have shown four; but three may, for some reasons, bepreferable. Each is marked EKE E is the back end, through which motionis imparted, and E the front end, through which the gripe upon the blankis transmitted.

The button-blank is marked m. I will describe it as a button having anequal. amount of swell on each face, though this may be varied.

The shaft or arbor B is hollowed from the front end backwardfor aconsiderabledistance. In the hollow interior is placed a long andsufliciently stiff spiral spring, G. In the front, and pressing backwardagainst the spiral spring, is an axially-sliding pin, H, having aconical end projecting between the ends E of the griping-levers.

I is a loosely-fitted ring applyin on the exterior of the arbor B. It isconnected rigidly with the pin H by a screw, J, which is tapped solidlyinto the latter. A longitudinal slot is produced in the arbor B, whichallows the pin H with its screw J to be moved backward and forward.

K is a hand-lever, turning on a center, It, and engaging in a groove inthe ring I. By moving'the hand-lever K, pressing the pin H inwardagainst the tension of the spring G, the griping-levers E E are set atliberty. Sm all flat springs L are employed, which move the ends Etoward each other, and cause the griping-arms E E to open. Thisliberates the blank, and it falls out. On inserting a new one, andmoving the hand-lever K in the proper direction, the pin H is thrustoutward by the force of the spring G. This causes the blank m to bestrongly griped.

The outer face of the chuck-body D may allow the button-blank to bepressed directly against it, or there may be any suitable adjustablepieceas the large smooth head of a screw-at that point to make anadjustable bearing for the blank, to provide for treating material ofdifferent thicknesses.

I have not represented the cutting-tool or any rest for it. The tool andrest may be of any ordinary form, and the cutter being operated by askillful button-maker, the outer face and rim are shaped with greatrapidity and perfection. After one face is thus finished, the blank isdropped by a proper movement of the hand-lever K to open the gripers,and is caught by the hand of the'attendant and turned and replaced. Nowthe nicely-rounded face instead of the flat face is presented backwardagainst the end of the arbor, and the end of the arbor having beenproperly recessed the swelled face of the blank enters therein. Now thegriping-levers, instead of taking hold, as at first, of the cylindricalsurface near one edge of the blank, take hold of the previouslyfinishedrounded edge at the middle of the edge. The flat face which is presentedoutward is next shaped by a proper manipulation of the cutter, and thefinished blank is dropped by another movement of the hand-lever K, and anew blank introduced.

It will be understood that on first introducing each blank the planeface presented backward against the arbor bears only at the rim, and theblank is held outward so far that the griping jaws or arms IE only takehold on the periphery near one edge; but it has a sufficient hold toallow the button to be strongly held, and a good chip cut by thecutting-tools. My device is much superior in this respect to the commonlathe, which takes hold of the blank at or near the center only. Whileit is thus held the front face and a little over the periphery isfinished. On turning this halffinished button and replacing it, thematerial which has been removed near the periphery allows the blank tosink deeper into the hollowed end of the arbor, and the jaws take holdproperly on the finished peri 'ihery.

Modifications may he made. Only two of the griping-levers E E or agreater number than four, may be employed.

The spring G, mounted centrally in the arbor, may be dispensed with, andthe gripingforce may be imparted through the hand-lever K, eitherdirectly or through some spring which acts thereon, and some of theadvantages of my invention may be realized. So

also the spring action may be dispensed with 'altogether, and asufficient hold may be ob' tained on the buttons by the direct force ofthe hand, or by any suitable mechanism.

Other means than the hollowed end of the arbor may be employed to allowthe blank to stand farther back, or be sunk farther into the arbor onthe second presentation than in the first. I can, if preferred, use twomachines, one for the first treatment and another for the secondtreatment of the button.

I can change the lever E E or change. the positions of the centers 0 toadapt the machine to different-sized buttons. It may generally be moreconvenient, however, to change the entire head or body, and to providedifferent sizes for different-sized buttons. The other parts may be thesame for all sizes of buttons. I prefer the arrangement herein shown.

The mounting of the jaws E E in slots within the head or body D, andoperating all by a central pin, H, allows the whole device to be verycompact.

The central position of the spring G relieves it from being disturbed bycentrifugal force.

My construction allows the parts to be short as well as close to thecenter, so that the arbor need overhang or project only to a smallextent.

The spriug-action to induce the closing of the gripers insures a justsufficient amount of force Without ever marking or marring the buttons.

I claim as my invention 1. In a button-lathe, a threaded arbor, B,carrying an adjustable wedge device and means for movingthe latteraxially at will, in combination with a detachable chuck-head or body, D,correspondingly threaded, and with clampingarms E E removable andexchangeable with the head, and adapted to serve as herein set forth. 7

2. The spring G and conical pin H, mounted axially in the arbor B, incombination with pivoted levers E E and chuck-body D, as hereinspecified.

In testimony whereof I have hereunto set my hand this 19th day ofFebruary, 1879, in the presence of two subscribing witnesses.

T. J. ROOKWOOD.

Witnesses:

THOMAS D. STETSON, H. A. J OHNSTONE.

